In modern microscope applications, imaging of biological samples can be combined with experiments, for example, on diffusion rates within the cytoplasm of biological cells, as described, for example, in C. de los Santos et al., 2015, Molecular Reproduction and Development, 82: 587-604, which is incorporated herein by reference in its entirety.
One experimental approach is FRAP (fluorescence recovery after photobleaching). Within an experimental area of the cell, especially within the cytoplasm, fluorescent labelled molecules are bleached by directing a high-intensity radiation beam to that sample area (hereinafter called region of interest). Observing the bleached region of interest for a period of time permits assessing the recovery of fluorescence in the region of interest (ROI) due to labelled molecules moving in to the ROI from the surrounding cytoplasm. The dynamics of the recovery of fluorescence enables conclusions on diffusion rates of labeled molecules in the cytoplasm. For conducting FRAP experiments and for obtaining meaningful and reliable experimental data, a useful region of interest should be identified and selected. Generally, ROI's are determined manually through human supervision, but this is time consuming and inefficient.
Other experimental approaches for studying cells include FLIP (Fluorescence Loss in Photobleaching), AB-FRET (Acceptor bleaching-Fluorescence Resonance Energy Transfer), experiments in which cell organelles/cell structures are destroyed or altered within a pre-defined region of interest of the cell.